JPS61130378A - Paint resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which is freed from the problems of odor and toxicity, can be cured at a low temp., has excellent initial tone and dryness and gives a coating film having excellent resistance to water, corrosion, chemicals and weather, by blending a copolymer with an epoxy compd. CONSTITUTION:A copolymer (A) having a weight-average MW of 1,000-1,000,000, contg. an average of at least two ammino groups per molecular and composed of 1-40wt% aminoalkyl (meth)acrylate unit of the formula [wherein R<1> is H, CH3; R<2> is a 1-6C (hydroxy)alkylene; R<3> is H, a 1-6C alkyl] and 99-60wt% ethylenically unsaturated monomer [e.g. methyl (meth)acrylate] unit is blended with an epoxy compd. (B) having an epoxy equivalent of 500 of below such as a condensate of (methyl)epichlorohydrin and a phenolic compd. as a hardener for component A in a ratio of the number of the H atoms of the amino groups in component A to the number of the epoxy groups in compo nent B of 0.5-3.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a coating resin composition with excellent curability.

BACKGROUND OF THE INVENTION Compositions made by blending epoxy resins and polyvalent amines are widely used as paints because of their good adhesion, hardness, flexibility, and chemical resistance. However, when polyvalent amines are used, they have strong odor and toxicity, dry the coating film slowly, and tend to cause blooming. When polyamide amine is used as a curing agent, the problems of odor and toxicity are greatly improved and the tendency of blooming is also reduced. However, the initial color tone is poor, and the drying properties and solvent resistance are poor.

On the other hand, it is also well known that acrylic resins having carboxyl groups in their side chains are cured with epoxy resins. However, high temperatures are required to cure the resin, making it uneconomical.

Problems to be Solved by the Invention The present invention solves the problems of odor and toxicity that are inevitable with conventional amine-cured epoxy resins, has a good drying curve, and can be dried at room temperature to 1.
To provide a coating resin composition that cures at a relatively low temperature of 20° C. and provides a good coating film.

Means for Solving the Problems As a result of various studies, the present inventors found that a copolymer composed of an aminoalkyl acrylate or aminoalkyl methacrylate unit and an ethylenically unsaturated unit, and a specific epoxy compound. It was discovered that a composition with excellent low-temperature curability can be obtained by combining epoxy compounds having the following properties, and based on this knowledge, the present invention was completed.

Specifically, the present invention provides (11 aminoalkyl acrylic L/
-r also L< is a coating resin composition comprising a copolymer composed of an aminoalkyl methacrylate unit and an ethylenically unsaturated 141 weight position, and (2) an epoxy compound having an epoxy equivalent of about 500 or less. Regarding.

The copolymer used in the present invention has the general formula (wherein
is hydrogen or a methyl group, 2 is an alkylene group or hydroxyalkylene group having 1 to 6 carbon atoms, and 3 is hydrogen or an alkyl group having 1 to 6 carbon atoms.Aminoalkylacryle-H: +L<A copolymer composed of laminoalkyl methacrylate units and ethylenically unsaturated monomer units.

Specific examples of aminoalkyl methacrylate units include aminomethyl acrylate, aminoethyl acrylate, aminopropyl acrylate, amino-n-butyl acrylate, aminohexyl acrylate, and N-methylaminoethyl acrylate. Acrylates such as ray-5,N-tert-butylaminoethyl acrylate, aminohydroxypropyl acrylate, aminomethyl methacrylate, aminoethyl methacrylate, avinol n-
Examples include units derived from methacrylates such as butyl acrylate, N-methylaminoethyl methacrylate, N-tert-butylaminoethyl methacrylate, and aminohydroxypropyl methacrylate. The content of these aminoalkyl acrylate or aminoalkyl methacrylate units in the copolymer is usually about 1 to 40%, preferably about 2 to 20%.
It is about as strong as a duck.

On the other hand, ethylenically unsaturated single abrasive units include evaporative methyl acrylate and ethyl acrylate.

Acrylates such as n-butyl acrylate and 2-ethylhexyl acrylate, methacrylates such as methyl methacrylate, ethyl methacrylate, and n-butyl methacrylate, fatty acid vinyl esters such as vinyl acetate and vinyl propionate, ethylene, propylene,
Aliphatic monoolefins such as isobutyne, styrene,
Examples include aromatic units such as vinyltoluene, etc., units derived from acrylonitrile, vinyl chloride, vinyl fluoride, etc. Among the above monomer units, copolymers mainly composed of acrylates and methacrylates are preferred in terms of weather resistance, yellowing resistance, and the like.

The copolymer may contain one type or two or more types of the above-mentioned single-vacuum units, and the proportion thereof is usually about 60 to 99% in the copolymer.
It is about 80 to 98% of the war song, preferably about 80 to 98%.

A copolymer composed of aminoalkyl acrylate or aminoalkyl methacrylate units and ethylenically unsaturated monomer units can be prepared using an aromatic solvent such as toluene,
A radical polymerization initiator such as an azobis-based or peroxide-based initiator is used in the presence of an alcohol-based solvent such as isopropanol or an ester-based solvent such as ethyl acetate, and if necessary, a chain transfer agent such as a mercaptan is used. It is produced by polymerization according to the method.

The copolymer contains at least two amino groups in one molecule, and has an average molecular weight of about 1,000 to 1,000.
About 0,000, preferably about 5,000 to 500.0
Approximately 00 is appropriate. The copolymer can be used as it is, but it may also be ketiminated with an aliphatic ketone or cyclic ketone, such as methyl ethyl ketone, methyl isobutyl ketone, or nclohextinone. A stable one-component composition can be obtained by combining this ketimine compound with an epoxy compound described below.

The epoxy equivalent used for curing the aforementioned copolymer is about 5
Examples of the epoxy compound having a value of 00 or less include a condensate of epichlorohydrin or methylepichlorohydrin and a phenol compound. An example of a phenolic compound in this case is commonly known as bisphenol A.
, bisphenol type such as bisphenol E11, novolak type polyfunctional phenol obtained by condensing formalin with phenol or cresol, and the like.

In addition, polyglycidyl ethers of polyoxyalkylene polyols such as polypropylene glycol, and glycidyl esters of aromatic or alicyclic polybasic acids such as diglycidyl phthalate and diglycidyl tetrahydrophthalate are also used. be able to.

All of these epoxy compounds have a molecular weight of about 500 or less.

Preferably, it has about 100 to 300 EBOKI 7 molds. When the epoxy resistance exceeds 500, the weather resistance of the coating film becomes poor.

These compounds can be used alone or as a mixture of two or more.

It is preferably about 1 to 2 degrees, particularly about 1 to 2 degrees.

The coating resin composition of the present invention obtained in this way is
For example, it can be used as a solution in an organic solvent such as ethyl acetate, isopropyl alcohol, methyl ethyl coke, luene, xylene, or the like, or as an emulsion dispersed in water. Further, stabilizers, fillers, etc. can be added as necessary.

Painting is usually done using an air spray gun or airless spray gun, or alternatively with a brush.

Can be applied using a roll coater, flow coater, tipping, etc.

Effects of the Invention The coating resin composition of the present invention can be cured at low temperatures ranging from room temperature to 120'C, so it can be used for plastics, wood, etc.
It can be advantageously used to form coating films in areas where heat treatment is not possible, such as concrete.

Of course, it can also be used to form coatings on metal materials and other fields that can be treated at high temperatures. The composition of the present invention has less odor than conventional amine-cured epoxy resin compositions.

There is little to no toxicity problem. In addition, the initial color tone and drying properties are excellent compared to amide-cured epoxy resin compositions. Furthermore, the composition of the present invention provides a coating film with excellent water resistance, corrosion resistance, straw resistance, and weather resistance, so that it can be used as a top coat.

The present invention will be explained in more detail below with reference to Examples and Comparative Examples. The parts and percentages shown in Reference Examples, Examples, and Comparative Examples are electric lamp parts and heavy electric lamp parts.

Reference Example Copolymer (A) 70 parts of methyl methacrylate, butyl acrylate? 1
A 3.0% toluene solution of a copolymer having a copolymer composition of 5 parts and 15 parts of aminoethyl methacrylate and a weight average molecular weight of 70,000.

Copolymer (B) 30 parts of methyl methacrylate, 5 parts of butyl methacrylate
A 35% toluene solution of a copolymer having an initial copolymer composition of 5 parts and 15 parts of aminoethyl methacrylate and a weight average molecular weight of 50,000.

Copolymer <C) 1-40 parts of methyl methacrylate, 40 parts of styrene, 10 parts of butyl acrylate, 10 parts of aminoethyl acrylate
35% toluene solution of a copolymer with a weight average molecular limit of 30,000.

Copolymer (D) The copolymer of (A) was dissolved in methyl in butyl ketone C and ketiminated to adjust the resin content to 30%.

Epoxy compound (A) Epoto-1-YD-128 (manufactured by Tobu Kasei ■, epoxy 11 (190) Epoxy compound CB) Epoxy compound CB) Epoto YH-301 (manufactured by Tobu Kasei ■, epoxy 150) Epoxy compound ( C) Bunacol EX-721 (manufactured by Nagase Chemical Industries, Ltd.).

Evokin 1154) Epoxy compound (DJ EPOTOTO YD-o 11 (manufactured by Tobu Kasei ■, Epoxy 450) Epoxy compound (DJ EBOTO t-YD-012 (manufactured by Tobu Kasei ■, Epoxy Company 650) Example 1゜Copolymer Combined (94 parts of AJ and 6 parts of epoxy compound (A) were added and spray-painted on a mild steel plate so that the cured film was 30 to 40 pm. The film was baked at 120°C for 20 minutes or 80°C for 30 minutes. Has a pencil hardness of 8H.

Goban eye test 100/100. Bending resistance test 2nd, Erichsen indentation test 8w1. It exhibited good solvent resistance with a specular gloss of 95. Table 1 shows some of the physical properties of the coating film baked at 120°C for 20 minutes. Moreover, this product gave a good cured coating film at room temperature for 5 days with a tank free time of 15 minutes.

Examples 2-7 Painting compositions were prepared using a series of copolymerized back pressure poxy compounds as shown in Table 1. Table 1 shows the properties of the coating film baked at 120°C for 20 minutes.

In addition, as Comparative Example 1, a copolymer (AJ and epoxy 5
Commercially available polyamide amine curing epoxy paint as Comparative Example 2, containing an epoxy compound (D) exceeding 00; Eponix #10 (Clear) [Dainippon Paint ■Cracked]
The properties of the cured coating film are shown in Table 1.

Example 8 Copolymer (76 parts of AJ, 19 parts of titanium dioxide)
/L/mi/l/, and an epoxy compound (A
) was added. This material has a hardened coating film of 40% on a mild steel plate.
The paint film was spray-painted to a thickness of ~50 μm and baked at 120°C for 20 minutes, resulting in a pencil hardness of 3H1 and excellent corrosion resistance (
No change after immersion in boiling water for 3 hours, immersion in 40℃ hot water for 1 month, immersion in 5% sulfuric acid for 120 hours at room temperature, and immersion in 5% caustic soda for 120 hours at room temperature], excellent solvent resistance (immersion in unleaded gasoline for 120 hours at room temperature, ethyl acetate) No change after 50 rubbings) Excellent stain resistance (magic ink black, red). The gloss retention rate after 700 hours of irradiation was 95% using an accelerated weathering tester (Q-Panel Co., USA).

Comparative Example 3 A coated board was prepared in the same manner as in Example 7 using the copolymer (A) and the epoxy compound CD).

Comparative Example 4 A plate coated with a commercially available polyamide amine curing epoxy paint Ebonix #10 (white) [manufactured by Dainippon Toyo ■] was prepared.

In both Comparative Examples 3 and 4, chalking occurred within 200 hours in the accelerated weathering test.

Example 9 A liquid resin containing 94 parts of the copolymer (D) and 6 parts of the epoxy compound (A) was stored at 40° C. for more than one month and could be used without any change. The coating film baked at 120° C. for 30 minutes had a pencil hardness of 2H and good solvent resistance.

(hereinafter referred to as “Kinpaku”)

Claims (1)

[Claims] A coating resin composition containing (1) a copolymer composed of aminoalkyl acrylate or aminoalkyl methacrylate units and ethylenically unsaturated monomer units, and (2) an epoxy compound having an epoxy equivalent of about 500 or less. thing.